Light bulb



FIG. 1 is top front perspective view of a light bulb according to my design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken line showing of portions of the bulb is included for the purpose of illustrating only and forms no part of the claimed design. 

CLAIM The ornamental design for a light bulb, as shown and described. 